Firestore:在 Web v9 中添加新数据的模式是什么? [英] Firestore: What's the pattern for adding new data in Web v9?

问题描述

我在很多地方看到，访问嵌套文档和集合的模式类似于 db.collection("users").doc("frank").collection("pets") 等

I have seen in many places that to access nested documents and collections the pattern is something like db.collection("users").doc("frank").collection("pets") etc.

这对我来说很有意义并且很容易理解.问题是，我的 (React) 项目是以 Web 版本 9 方式设置的.我一遍又一遍地梳理了文档，除了在 Y 集合中引用 X 文档之外，看不到任何内容.

This makes a lot of sense to me and is easy to understand. The trouble is, my (React) project is set up in the Web version 9 way. I've combed the docs over and over and can't see anything that goes beyond referencing X doc in Y collection.

我需要引用用户 >用户名>一些集合

I need to reference Users > uid > someCollection

但在 Web 版本 9 中我只能这样做:doc(db, "users", uid)

But in the Web Version 9 way I can only do: doc(db, "users", uid)

我如何更深入?

推荐答案

如果您想获得:

• a CollectionReference，然后使用 collection():

• a CollectionReference, then use collection():

const myCol = collection(db, "collection", "doc1", "sub-col1")

• a DocumentReference，然后使用 doc():
• a DocumentReference, then use doc():

const myDoc = doc(db, "collection", "doc1", "sub-col1", "sub-doc1")

概念保持不变.文档路径具有偶数个段，例如col/doc/sub-col/sub-doc 而集合的路径有 odd 例如col/doc/sub-col.

The concept remains same. The path to a document has even number of segments e.g. col/doc/sub-col/sub-doc while path to a collection has odd e.g. col/doc/sub-col.

如果传入的参数数量无效，这两种方法都会抛出错误.

在命名空间版本 (v8) 中，它曾经看起来像:

In the name-spaced version (v8), it used to look like:

// DocumentReference
firebase.firestore().doc("col/doc/sub-col/sub-doc")

// CollectionReference
firebase.firestore().collection("col/doc/sub-col")

本质上，您不断向相同的 doc() 或 collection() 方法添加路径段.

In essence, you keep adding path segments to the same doc() or collection() methods.

doc(firestore: Firestore, path: string, ...pathSegments: string[]):
// You can also use spread operator with an array

---

扩展运算符示例:

---

An example with spread operator:

const myDocPath = "users/user1/posts/post1/comments/comment1"
const docRef = doc(db, ...myDocPath.split("/"))

如果将 spread operator 与 split() 一起使用，请确保没有任何前导或尾随斜线.

Just make sure you don't have any leading or trailing slash if using spread operator with split().

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